An active device array substrate for saving material cost includes a substrate, scan lines, data lines, a thin film transistor, a color filter layer, a transparent conductive layer, an insulating layer and a pixel electrode. The color filter layer covers and contacts the scan lines, data lines and the thin film transistor. The transparent conductive layer is disposed on the color filter layer and electrically isolated from the scan lines, the data lines and the thin film transistor by the color filter layer. The insulating layer covers the transparent conductive layer. The pixel electrode is disposed on the insulating layer and connected to the thin film transistor.